Premium
1‐Pyrrolidine Dicarbodithioate Based Electrodes for Determination of Iron(III) in Lubrication Oil
Author(s) -
Zareh Mohsen M.,
Ismail Ismail F. A.,
Abd ElAziz Mohamd H.
Publication year - 2010
Publication title -
electroanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.574
H-Index - 128
eISSN - 1521-4109
pISSN - 1040-0397
DOI - 10.1002/elan.200900550
Subject(s) - electrode , detection limit , chemistry , analytical chemistry (journal) , selectivity , linear range , ionophore , standard hydrogen electrode , reference electrode , nuclear chemistry , inorganic chemistry , membrane , electrolyte , chromatography , organic chemistry , biochemistry , catalysis
The lipophillic ammonium salt of 1‐pyrrolidine dicarbodithioic acid (PCDT) (I) was introduced as a new selective ionophore for an iron selective electrode. In addition, the effect of immobilization of 18‐crown‐6 (18CE6) (membrane type‐II), on the electrode performance was discussed. The slope of the PCDT‐based (I) electrode was (20 mV/decade). The linear concentration range was (10 −5 –10 −1 M) after one day doping. The detection limit for electrode type‐(II) was (1.3×10 −6 M). For membrane with only 18CE6 (type‐III) the linear range and the detection limit were improved (10 −5 –10 −1 M and 3.2×10 −6 M, respectively). The pH‐range was between 5–11 for type‐II, and III electrodes, while it was 7–11 for type‐I electrode. Most of the common cations were tested for the evaluation of the electrode selectivity with correlation to the ionic radii of the tested cations. Among them only Ag + and Pb 2+ were the real interference for type‐III electrode. Application of using the electrode for the determination of iron in lubrication oil samples was performed with RSD (1.77–2.7%) and (1.01–2.3%) for type‐II and III electrodes, respectively. The corresponding recovery ranges were (93.0–99.9%) and (96.3–100%). The obtained results were compared to those of an atomic absorption spectrophotometric method.